Anyone else use these. It's just Hal comping to standards in a very hip way. I use to practice to these for hours years ago and forgot about them. I found them the other day and started to play to them. They are so much hipper than the Aebersolds. Hal plays all sorts of crazy harmonic and rhythmic stuff on them it really challenges you to listen. there are 3 books and play along CD's. Great Stuff.